Molding machine



Nov; 1, 1938. R w E 2,135,372

MOLDING MACHINE Filed May 20, 1937 2 Sheets-Sheet 1 NOV. 1, 1938. R H, wlEHSNER 2,135,372

MOLDING MACHINE Filed Ma 20, 1957 2 Sheets-Sheet 2- iii I #wavrM Patented Nov. 1, 1938' UNITED STATES PATENT OFFICE MOLDING MACHINE Application May 20, 1937, Serial No. 143,682

1 Claim.

The present invention relates to improvements in molding machines, more particularly of the drop pattern type.

The principal object of the present invention is to provide simple, reliable and eflicient mechanism for automatically holdingthe flask frame in elevated position while the pattern plate is dropped, and to provide simple, reliable and eflicient means for permitting the flask frame to be lowered to its normal position. Another object is to so construct and arrange the parts that the machine may be operated as a flask lift machine; or, in other words, to provide a machine which can be operated at will either as a pattern drop or flask lift machine.

Other objects of the invention will appear from the following description at the end of which the invention will be claimed.

Generally stated, the invention consists in an oscillating latch mounted on the head of the machine and adapted to stop the down travel of the flask frame automatically and to be reset manually. The invention also comprises the improvements to be presently described and finally claimed.

In the following description reference will be made to the accompanying drawings forming part hereof and in which:

Figure 1 is an elevational view partly in central section illustrating a molding machine embodying features of the invention.

Fig. 2 is a side elevational view of the same; and

Fig. 3 is a top or plan View illustrating in dotted lines, as well as in full lines, a latch embodying features of the invention.

Referring to the drawings, l indicates a flask frame and 2 indicates a drop plate or drop pattern plate. These parts are movable upwards and downwards as a unitary structure, and also as separate units. There is nothing particularly new about this and the means for this purpose in the embodiment selected for illustration from among other embodiments will be described. The frame of the machine is provided with a squeezer cylinder 3 and piston 4. The piston 4 carries the pattern plate 2 thru the intervention of the elements 5. The piston 4 also carries the guide cylinder 5 and center draw plunger 6. The plunger 6 carries the stool plate 1 and stool structure 8, to which is connected the flask frame I. The flask a, mounted on the flask frame I, and properly filled with sand and with all the other parts in the positions shown in the drawings can be lifted against the ramming block 9 carried by the yoke I so as to squeeze or otherwise ram the sand. This is done by the introduction of fluid under pressure into the cylinder 3 by way of the port ll.

The fluid pressure raises the piston 4 and all of the parts connected therewith. In drop drawing the pattern, the flask frame I and flask a, are arrested in their descent and the rest of the structure descends as above described. The

centre draw guide cylinder and plunger 6 may contain oil and they operate to guide the pattern plate in its descentand the oil limits its speed. The guide pin l2, Fig. 2, serves a like guiding purpose. Having thus indicated certain parts of one type of molding machine to which the invention is applicable a description of the latter will now be given.

i3 are screw stops operatively held fixed by brackets l4 connected to the cylinder 3, or to some fixed part of the machine. The cylinder 3 supports the stool plate 1 and flask frame when the parts are in lowest position as shown in Fig. 1. I8 is a latch centrally pivoted, spring pressed and arranged for oscillation. As shown the latch I8 is pivoted to the neck of the plunger 6 and it is pressed by a spring l5, or other suitable device such as a pneumatic device. Its movement is limited by stops I6 and I1, Fig. 3. The ends of the latch l8 are, when the parts are in the position shown in Fig. I, pressed against opposite faces of the side walls of the screw stops 13 which do not contact with stool plate I. When the structure carried by the piston 4 is raised to bring the sand in contact with the ramming block 9 the latch I8 is carried upward until its ends clear the screw stops l3, whereupon it is turned by its spring l5 or pneumatic device into line with the tops of the screw stops I3 and against its stop IS. The latch remains in this position during the upward movement of the parts carried by the piston 4. Upon downward movement of the piston 4 the ends of the latch l8 which are shown as provided with pads l9 rest upon the upper ends of the screw stops I3 and under the stool plate I and in that way check the descent of the flask frame and flask a. During further descending movement of the piston 4, the guide plunger 6, by reason of its weight and load, moves in its cylinder and the pattern plate 2 descends drawing the patterns out of the flask a. The oil in the cylinder 5 checks and regulates the speed 7 tion by moving the ends of the latch l8 oif the ends of the screw stops I 3 and against their lateral faces ready for another operation. This is done by means of a counterbalanced foot lever 20 having an arm 2| which projects into range of an extension 22 on the latch I8.

In the foregoing description reference has been 7 made to dropping the pattern out of the flask;

however the flask can be lifted off the pattern.

In fact the machine can be operated either way;

To lift the flask from the pattern, the latch I8 is held out of action or permitted to remain out of action, for example by releasing the spring IS, the piston 4 is in the position shown in the drawings and pressure is applied to the piston 6 in order to lift it along with the flask frame I.

One way to do this is to dispense with the hole 23, and to provide a hole in the lower wall of the cylinder 5 for example, at the point indicated at 24, and in that case the space inside of the piston 4, is filled with oil'to the top of which pressure is applied to lift the piston 6, and the pressure is relieved to permit the piston 6 to descend at regulated speed.

It will be understood that when the machine is to beoperated asa pattern drop machine only,

the oil may be confined to the cylinder 5 'and to e the hollow piston 6, and by flowing through the V hole 23 it regulates the descent of the plunger 6 and parts carried thereby. Whenthe machine 7 is t'obe used either .as a pattern drop or flask lift machine the hole 23 is replaced by a hole at 24 and v the cylinder 4 is filled with oil. When the machine is intended for convertible use, and is being *used as a pattern dropmachine, the oil flows from the cylinder 5 through the hole at 24 into the cylinder 4, and when the machine is used as a flask lift machine air pressure is put upon the oil in the cylinder 4 and-oil under pressure passes through the hole at 24, and piston 6 andparts carried thereby are lifted. V

It will. be obvious to those skilled in the art" to which the invention relates that modifications may-be made in details of construction and arters or otherwise than the prior state of the art and the appended claim may require. a

I claim: A latch for a molding machine having a "stastops or to be interposed between the tops of said screw stops and said flask frame structure so as to support said flask frame structure, means stressing said latchaboutits pivot towards said screw stops, stops limiting the pivotal movement of said latch about its pivot,- and a counter-balanced foot-operated lever mounted on said stationary frame and having a portion arranged for engage- V ment with a portion of said latch andoperable to move said latch against'the stress of said means. V t

RAYMOND H. WIEHSNEB.

' tionary frame, a flask frame structure movable e' rangement without departing from the spirit of 10- p the invention whichis not limited as to such mat- 

